Release announcement at sup-devel and sup-talk mailinglists (since rubyforge
appears to be down at the moment):

Hi all,
Sup 0.15.0 is out, get it at rubygems:
$ gem install sup
(detailed installation instructions in the wiki [1])
News, please at least skim through:
* Maildir Syncback has now been merged into main sup! This is a
long-time waiting feature initially developed by Damien Leone,
then picked up by Edward Z. Yang who continued development. Additionally
several others have been contributing.
Eventually, recently, Eric Weikl has picked up this branch, modernized
it to current sup, maintained it and gotten it ready for release.
Main authors:
Damien Leone
Edward Z. Yang
Eric Weikl
Not all of the features initially proposed have been included. This is
to maintain compatibility with more operating systems and wait with
the more daring features to make sure sup is stable-ish.
This is a big change since sup now can modify your mail (!), please
back up your mail and your configuration before using the maildir
syncback feature. For instructions on how to migrate an existing
maildir source or how to set up a new one, refer to the wiki:
https://github.com/sup-heliotrope/sup/wiki/Using-sup-with-other-clients
It is possible to both disable maildir syncback globally (default:
disabled) and per-source (default: enabled).
* Sup on Ruby 2.0.0 now works - but beware, this has not been very throughly
tested. Patches are welcome.
* We are now using our own rmail-sup gem with fixes for Ruby 2.0.0 and
various warnings fixed.
* sup-sync-back has been renamed to sup-sync-back-mbox to conform with
the other sync-back scripts.
* You can now save attachments to directories without specifying the full
filename (default filename is used).
* Various encoding fixes and minor bug fixes
Important: If you are upgrading from a Sup version prior to 0.14.0
please read the migration instructions in the wiki [0].
Please report any issues you encounter to our GitHub issue tracker [2].
Thanks to all who have contributed to sup either with code [3] or
testing!
Cheers, Gaute
[0] https://github.com/sup-heliotrope/sup/wiki/Migration-0.13-to-0.14
[1] https://github.com/sup-heliotrope/sup/wiki
[2] https://github.com/sup-heliotrope/sup/issues
[3] https://github.com/sup-heliotrope/sup/blob/release-0.15.0/CONTRIBUTORS